I submitted my resume to my university's career website and subsequently received an email to complete a coding challenge online. This challenge was used to determine whether I would receive an on-campus interview. It consisted of two questions, both of which I have included below. I finished the first question and completed half of the second.

Following this, I secured an on-campus interview, which was conducted in a pair-coding style. We implemented a least-recently-used cache in Java. It was an enjoyable experience, and I was able to Google syntax I was unfamiliar with, ultimately getting the code to run.

A short while later, I received an email to schedule an on-site interview at Square in San Francisco. This involved breakfast, three pair-coding interviews, lunch, several talks, coffee at Sightglass, and then concluded.

The three questions I was asked were:

• Find all prime numbers under a given number.
• Fraud detection: If two merchants have swiped the same card, they are part of the same component. Find the size of the component.
• Parse TVL bytes and return the cardholder name.

I struggled particularly with the last question. I was notified of no offer after a week.

coefficients line (a’s), lines of values from transactions (x’s) y = a0 + a1x1 + a2x2 + ... + aN*xN y <= 0 not fraud, y > 0 suspect fraud output fraud/not fraud for each line of N lines

input: two numbers, N and M, which define an NxM grid start at top left corner of grid (1,1):

• step forward
• turn right
• if space in front of you is out of board or you already walked on it, turn right keep going until you can’t walk anymore output is number of steps you take before stopping.